Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, Leuven, Belgium.
Dent Mater. 2010 Jun;26(6):524-32. doi: 10.1016/j.dental.2010.01.010. Epub 2010 Mar 3.
The low-shrinking composite composed of combined siloxane-oxirane technology (Filtek Silorane, 3M ESPE, Seefeld, Germany) required the development of a specific adhesive (Silorane System Adhesive, 3M ESPE), in particular because of the high hydrophobicity of the silorane composite. The purpose of this study was to characterize the interfacial ultra-structure at enamel and dentin using transmission electron microscopy (TEM).
Non-demineralized/demineralized 70-90 nm sections were prepared following common TEM specimen processing procedures.
TEM revealed a typical twofold build-up of the adhesive resin, resulting in a total adhesive layer thickness of 10-20 microm. At bur-cut enamel, a tight interface without distinct dissolution of hydroxyapatite was observed. At bur-cut dentin, a relatively thin hybrid layer of maximum a few hundreds of nanometer was formed without clear surface demineralization. No clear resin tags were formed. At fractured dentin, the interaction appeared very superficial (100-200 nm). Distinct resin tags were formed due to the absence of smear plugs. Silver-nitrate infiltration showed a varying pattern of both spot- and cluster-like appearance of nano-leakage. Traces of Ag were typically detected along some part of the enamel-adhesive interface and/or between the two adhesive resin layers. Substantially more Ag-infiltration was observed along the dentin-adhesive interface of bur-cut dentin, as compared to that of fractured dentin.
The nano-interaction of Silorane System Adhesive should be attributed to its relatively high pH of 2.7. The obtained tight interface at both enamel and dentin indicates that the two-step self-etch adhesive effectively bridged the hydrophilic tooth substrate with the hydrophobic silorane composite.
由硅氧烷-环氧化合物技术（Filtek Silorane，3M ESPE，德国 Seefeld）组成的低收缩型复合材料需要开发一种特殊的胶粘剂（Silorane 系统胶粘剂，3M ESPE），特别是因为硅氧烷复合材料的高疏水性。本研究的目的是使用透射电子显微镜（TEM）来描述牙釉质和牙本质的界面超微结构。
按照常规 TEM 标本处理程序制备非脱矿/脱矿的 70-90nm 切片。
TEM 显示出胶粘剂树脂的典型双层堆积，导致总胶粘剂层厚度为 10-20μm。在切割牙釉质时，观察到无明显羟基磷灰石溶解的紧密界面。在切割牙本质时，形成了厚度相对较薄的混合层，最大厚度为几百纳米，没有明显的表面脱矿。没有形成明显的树脂突。在断裂牙本质中，相互作用显得非常表面化（100-200nm）。由于缺乏玷污层，形成了明显的树脂突。硝酸银渗透显示出纳米泄漏的点状和簇状出现的不同模式。Ag 痕迹通常沿牙釉质-胶粘剂界面的一部分和/或两个胶粘剂树脂层之间检测到。与断裂牙本质相比，在切割牙本质的牙本质-胶粘剂界面观察到更多的 Ag 渗透。
Silorane 系统胶粘剂的纳米相互作用应归因于其相对较高的 pH 值 2.7。在牙釉质和牙本质上均获得的紧密界面表明两步自酸蚀胶粘剂有效地将亲水牙齿基质与疏水性硅氧烷复合材料桥接起来。
